On the foggy morning of July 2, 2014, a Delta II rocket carrying NASA’s Orbiting Carbon Observatory-2 (OCO-2) roared off the launch pad at Vandenberg Air Force Base in California. The landmark satellite will survey carbon dioxide in Earth’s atmosphere and is expected to provide insight into how the planet is responding to the increasing concentration of carbon dioxide in the atmosphere.

While sensors on the ground have monitored carbon dioxide for decades, key questions about how carbon cycles between Earth’s atmosphere, ocean, and land surfaces persist. For instance, it isn’t well understood how a significant portion of carbon dioxide emissions get recycled to other parts of the planet rather than remaining in the atmosphere.

“Half of the carbon dioxide we’re dumping into the atmosphere every year is disappearing somewhere,” explained OCO-2 project scientist David Crisp during a press conference prior to the launch. “We know from measurements that about a quarter of it is dissolving into the ocean, and we assume that the other quarter is going into the land biosphere somewhere—into forests, into trees, into grasslands—but we don't know where. It is absolutely critical that we learn what processes are absorbing carbon dioxide because we need to understand how much longer they might continue to do us that great favor.”

There are also unanswered questions about why the atmosphere holds more carbon dioxide during some years than others. “Sometimes almost 100 percent of the carbon dioxide we put into the atmosphere stays there; sometimes almost none does. We don't know why,” said Crisp. “We need to understand these processes in order to understand how carbon dioxide will build up in our system in the future, and how we might manage carbon dioxide if that’s what policy makers decide to do.”

NASA photographer Bill Ingalls captured this photograph a few seconds after liftoff at 5:56 a.m. Eastern time. The video, shot by NASA TV, shows the first two minutes of the rocket’s flight. The launch was from the West Coast so the spacecraft could enter a polar orbit, a flight path that will see it cross over the Arctic and Antarctic regions during each revolution and get a complete picture of the Earth. It will fly about 438 miles (705 kilometers) above the planet’s surface.